In a reversible reaction at equilibrium between two reactants,if the concentration of the reactants is doubled,the equilibrium constant ..........

$A$ liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased.
$(a)$ What is the initial effect of the change on vapour pressure?
$(b)$ How do rates of evaporation and condensation change initially?
$(c)$ What happens when equilibrium is restored finally and what will be the final vapour pressure?

Equilibrium is a steady state,but it is dynamic in nature. What is the meaning of this statement?

In the chemical reaction $A \rightleftharpoons B$,the system will be known to be in equilibrium when:

For the reaction $2HI_{(g)} \rightleftharpoons H_{2(g)} + I_{2(g)}$,the equilibrium constant $K$ at room temperature is $2.85$,and at $698 \ K$ it is $1.4 \times 10^{-2}$. This indicates that:

The equilibrium constant for the reaction $N_{2(g)} + O_{2(g)} \rightleftharpoons 2 NO_{(g)}$ is $4 \times 10^{-4}$ at $2000 \ K$. In the presence of a catalyst, the equilibrium is attained $10$ times faster. Therefore, the equilibrium constant, in the presence of the catalyst at $2000 \ K$ is: